Male/Male Relationships

Males have a dominance hierarchy, which is largely determined by size (which increases with age) (Estes 1991). When two non-musth males have an aggressive interaction over a mate, size determines the winner. When a musth male and a non-musth male compete over a mate, the state of musth determines the winner. When two musth males have an aggressive interaction over a mate, size determines the winner. Aggressive interactions rarely escalate into fights (Poole 1989). Aggressive behaviors include ear flapping (which is also use for thermoregulation), head jerking, head tossing, and the forward-trunk-swish. An elephant indicates submission by writhing its trunk and lowering its head while moving backwards and sideways (Estes 1991).
Non-musth bulls rarely have aggressive encounters. Dominance is determined by size. Bulls will allow a larger bull preferential access to a resource, such as a watering hole (Moss 1982). When two bulls meet that are approximately the same size, they will interlock tusks and/or trunk bases. The bull that holds his head higher establishes dominance. Non-musth bulls sometimes live in bachelor herds, especially young bulls. Some bulls seem to have one or more bulls that they have a closer association with (Estes 1991).